When does a nationally rising dance company stop looking "local" to the folks back home? For Robert Moses' Kin, that moment arrived Thursday at the Yerba Buena Center for the Arts, where the troupe continues its Bay Area Now engagement tonight. Sure, in recent years Moses' sui generis style of fierce, alternately street-wise and balletic movement has graced the prestigious Jacob's Pillow and New York's Fall for Dance Festival, but in San Francisco, it's been crammed onto small stages where it often looks cluttered and frenetic. In the Novellus Theater, Moses' dancers have space, and they seize it.

The current run delivers more than 60 minutes of hard-driving, sharp, detailed dancing that surely projects to the last row of seats as powerfully as it does to the first. It is an orgiastic outpouring of luscious human motion. And yet, it starts to lose impact in about 20 minutes.

The problem is programming. For the show's first half, Moses has stacked two pure-movement dances set to his own music. By far the better is "Approaching Thought," from earlier this year, with its gung-ho Wild West guitar motif. Caitlin Kolb storms center stage to gesture madly at an impassive Brendan Barthel, her shrugging shoulders and roiling spine so fearsome you can practically see four-letter words in thought bubbles above her head. Two other couples join them, charging from the corners, then swirling the stage in ever more tension-building formations before Kolb has the last say. It's tight, masterful in form, and it's all over in 10 minutes.

Would that "Toward September," the premiere and YBCA commission, had such focus. YBCA markets this as a dance "about the divine impulse behind artistic creation," and I thought at first I caught a glimpse of something ecclesiastical within it. The 10 dancers are clothed in a shade of brown that recalls Franciscan robes, their tableaux-like arrangements suggesting religious iconography, as two women are draped like Christ from the men's linked arms.

But the imagery quickly diffuses as the dance follows the meanderings of Moses' music, from church bells into a morass of worming bass, an interlude of '70s groove, and closing piano chords. Moses could have divided "Toward September" into three pieces, probably with better results.

The closing "Jokes Like That Can Get You Killed," from last year, is simply a mess, never rising in sophistication above its grab bag of easy targets. Bobbleheaded animations of George Bush, Gavin Newsom and Anna Nicole Smith bumble across a screen as Moses and David Worm's score remixes porn moanings and choice media absurdities like Don Imus' mea culpa. The dancers do not have such rich material to work with here, but they never let on, led by the whiplash Amy Foley and several compelling new company members, including Norma Fong and Michael Velez.

Robert Moses' Kin belongs on the YBCA stage. I only wish they were dancing Moses' best works.